Bleaching agent particles encapsulated in a water soluble material

• US 20070093402A1
• Filed: 10/04/2006
• Published: 04/26/2007
• Est. Priority Date: 04/15/2004
• Status: Active Grant

• Current Assignee: Henkel AG & Co KGaA
• Original Assignee: Henkel AG & Co KGaA
• Inventors: Meier, Frank, Speckmann, Horst-Dieter, Werner, Helga, Assmann, Georg
• Granted Patent: US 7,897,556 B2
• Time in Patent Office: Days
• US Class Current: 510/302
• CPC Class Codes: C11D 17/0039 Coated compositions or coated components in the compositions, (micro)capsules
• CPC Class Codes: C11D 3/3753 Polyvinylalcohol; Ethers or esters thereof
• CPC Class Codes: C11D 3/3945 Organic per-compounds C11D3/3902 takes precedence

Abstract

The invention relates to encapsulated bleaching agent particles. Said particles consist of a core that contains a bleaching-agent active ingredient and a coating of water-soluble material that at least partially surrounds said core, the core containing peroxocarboxylic acid and the coating material containing polyvinyl alcohol. The particles can be produced by introducing a particulate peroxocarboxylic acid into a fluidized bed, by spraying an aqueous solution containing polyvinyl alcohol onto said bed and by subsequent drying or spray drying.

Claims

1. An encapsulated bleaching agent particle consisting of a core that comprises active bleaching agent and a coating of water-soluble material that at least partially surrounds this core, wherein the core comprises peroxycarboxylic acid and the coating material comprises polyvinyl alcohol.

2. The particle according to claim 1, wherein the coating material additionally comprises an acid.

3. The particle according to claim 2, wherein the proportion by weight of polyvinyl alcohol to acid in the coating material is in a ratio of 1,000:

1 to 1;

2.

4. The particle according to claim 1, wherein the core comprises carrier material in addition to the peroxycarboxylic acid, said carrier material being identical to the coating material.

5. The particle according to claim 1, wherein coating material comprises 5 wt. % to 50 wt. % of the encapsulated particle.

6. The particle according to claim 1, wherein the content of peroxycarboxylic acid is 20 wt. % to 90 wt. %.

7. The particle according to claim 1, wherein the peroxycarboxylic acid is seleted from the group consisting of peroxyformic acid, peroxyacetic acid, peroxypropionic acid, peroxyhexanoic acid, peroxybenzoic acid and its substituted derivatives such as m-chloroperoxybenzoic acid, the mono- or di-peroxyphthalic acids, 1,12-diperoxydodecanedioic acid, nonylamidoperoxyadipic acid, 6-hydroxyperoxyhexanoic acid, 4-phthalimidoperoxybutanoic acid, 5-phthalimidoperoxypentanoic acid, 6-phthalimidoperoxyhexanoic acid, 7-phthalimidoperoxyheptanoic acid, N,n′

-terephthaloyl-di-6-aminoperoxyhexanoic acid and their mixtures.

8. The particle according to claim 7, wherein the peroxycarboxylic acid is 6-phthalimidoperoxyhexanoic acid.

9. A detergent or cleansing agent comprising encapsulated bleaching agent particles consisting of a core that comprises active bleaching agent and a coating of water-soluble material that at least partially surrounds this core, wherein the core comprises peroxycarboxylic acid and the coating material comprises polyvinyl alcohol.

10. The detergent or cleansing agent of claim 9, wherein the coating material further comprises an acid.

11. The detergent or cleansing agent according to claim 10, wherein the proportion by weight of polyvinyl alcohol to acid in the coating material is in a ratio of 100:

1 to 1;

2.

12. The detergent or cleansing agent according to claim 9, wherein the core comprises carrier material in addition to the peroxycarboxylic acid, said carrier material being identical to the coating material.

13. The detergent or cleansing agent according to claim 9, wherein the coating material comprises 5% to 50 wt. % of the encapsulated particle.

14. The detergent or cleansing agent according to claim 9, wherein the content of peroxycarboxylic acid is 20 wt. % to 90 wt. %.

15. The detergent or cleansing agent according to claim 9, wherein the peroxycarboxylic acid is selected from the group consisting of peroxyformic acid, peroxyacetic acid, peroxypropionic acid, peroxyhexanoic acid, peroxybenzoic acid and its substituted derivatives such as m-chloroperoxybenzoic acid, the mono- or di-peroxyphthalic acids, 1,12-diperoxydodecanedioic acid, nonylamidoperoxyadipic acid, 6-hydroxyperoxyhexanoic acid, 4-phthalimidoperoxybutanoic acid, 5-phthalimidoperoxypentanoic acid, 6-phthalimidoperoxyhexanoic acid, 7-phthalimidoperoxyheptanoic acid, N,n′

-terephthaloyl-di-6-aminoperoxyhexanoic acid and their mixtures.

16. The detergent or cleansing agent according to claim 9, wherein the peroxycarboxylic acid is 6-phthalimidoperoxyhexanoic acid.

17. A process for manufacturing encapsulated bleaching agent particles, consisting of a core that comprises active bleaching agent and a coating of water-soluble material that at least partially surrounds this core, comprising the steps of introducing a particulate peroxycarboxylic acid into a fluidized bed to form particles, spraying onto the particles an aqueous solution that comprises polyvinyl alcohol to form the coating, and drying the coated particles.

18. A process according to claim 17, wherein the temperature of the bleaching agent particles does not exceed 50°

C. during the steps of spraying on the aqueous solution and drying.

20. A detergent or cleansing agent comprising bleaching agent particles made according to the process of claim 17.

19. A process for manufacturing encapsulated bleaching agent particles consisting of a core that comprises active bleaching agent and a water-soluble material that at least partially surrounds this core, by spray drying an aqueous preparation that comprises peroxycarboxylic acid and polyvinyl alcohol.